Leo Kliesen is a character that first appeared in Tekken 6 and in the following games. Leo made the first appearance in the official Tekken 6 trailer battling Armor King. Leo is an orphan who lost the parents under the circumstances that police would not want to investigate. Leo play style is also intended for beginners and veterans alike. Leo's fighting style is Bajiquan.
Leo's parents were a famous male spelunker and a top female executive of the biotech firm, G Corporation.
Leo’s father disappeared during an exploration when Leo was a child, but even so, Leo tried to be just him. Leo grew up to be a straight and narrow person, but Leo's mother's murder changed everything.
Saddened by the tragic event, Leo shut everyone out. Some time later, the police inconclusively ended the murder investigation without explanation but Leo continued to try to crack the case. Not long after starting this mission, Leo discovered the existence of a person regarded as a hero of the G Corporation - a man by the name of Kazuya Mishima. Suspecting him of committing the murder, Leo sought revenge but found it impossible to get near Kazuya due to his newly acquired status within the G Corporation.
However, Leo heard news of The King of Iron Fist Tournament 6 being held by the Mishima Financial Group. Finding out that Kazuya would be participating in it, Leo signed up, thinking that it would be the only chance for revenge.
Leo's closing cinematic takes place at the grave of the character's mother, where Leo finds an envelope labeled with "Dear Leo," and then quickly turns around to find that no one is in sight.
The gender of Leo is left open to the viewer. The character is voiced by a female in T6 (however the person who voiced Leo in TTT2 and TK7 is still unknown) and female hair sets are available in character customizations indicating that the character could be female yet is found in the male section of the Tekken 6 Art Book and the game provides for the character male clothes therefore indicating that the character is male. Upon question Namco said that they wanted a character who could be loved by the public no matter what their gender. It was assumed that the character was 12 years old until Namco confirmed the character was 19.
Tekken 6: Bloodline Rebellion
Leo remains unchanged mainly in variants of the game. However in Bloodline Rebellion Leo's item move was changed, in Tekken 6 the move is to fire a flare into the air with a pistol whereas in Bloodline Rebellion the move was changed to hitting the opponent with a mace.
For her ending, she pays a visit to her mother's grave and finds a note from her father. We don't get to see him directly, so Leo looks up determined to learn the conditions her mother's death.
Tekken Tag Tournament 2
Leo infiltrates a G Corp train wanting to learn what happened to her mother. Sneaking into a guard's cabin, she gets on the laptop and learns her mother Emma Kliesen was supervising the Mishima Zaibatsu's Devil Gene project to grant a subject immeasurable strength. Twenty years before, this was shut down after a number of fatal accidents. Heihachi had ordered the production of a subject with a hybrid gene NT01, who would soon become Steve Fox. Emma Kliesen reported the subject had died. Leo is shocked that Emma was employed by the Zaibatsu. She copies the information to a USB but is cornered by more suits aiming guns at her. Leo vows to find those who killed her mother, and rappels off the train.
- Leo's gender and sex is left ambiguous by Namco. Leo could be customized with female hairstyle yet is placed in the male section of the Tekken art book and have got access to male customizations.
- Leo's original concept was a female character called Eleonore Kliesen. Because of the masculine appearence, the concept has been discarded and the name Leo and the neutral gender have been given to the character before the release of Tekken 6 in arcades.
- Leo's surname, which is probably "Kliesen" is revealed in the power is everything trailer. It is shown on her mother's grave.
- Leo is voiced by Veronica Taylor, the same person who voices Ash Ketchum in the Pokemon series.
- It is unknown whether Leo's father is dead or not. It is only mentioned that he disappeared in one of his explorations.
- Under the eagle of Leo's parka you can read 'Die Lebensspanne ist dieselbe egal ob man sie lachend oder weinend verbingt' (The lifespan is the same, whether it is spent laughing or crying), which is a Chinese wise saying.
- Joined the Tekken 6 tournament to hunt Kazuya Mishima.
- Leo uses male pronouns in Tekken 7 despite the Japanese bio uses neutral pronouns or repeat the name.